


My Favorite Undertale Au Skelebros X Reader

by Foxy_Springtrap



Category: Echotale - Fandom, Mafiatale - Fandom, Outertale - Fandom, Underfell - Fandom, Undertale, underswap
Genre: Horrortale Chapter, Multi, Soulmate Chapter, Undertale Chapter, oneshot book
Language: English
Status: In-Progress
Published: 2020-08-28
Updated: 2020-11-01
Packaged: 2021-03-07 02:07:10
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 3,699
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26149168
Author URL: https://archiveofourown.org/users/Foxy_Springtrap/pseuds/Foxy_Springtrap
Summary: I want to write a oneshot book with my favorite undertale Au's.In order from favorite to ehh,1. UnderTale2. UnderSwap3. UnderFell4. SwapFell5. HorrorTale6. EchoTale7. DanceTale8. MafiaTale9. BirdTaleAgain, no lemons! Only limes!Idk if I'll do requests
Relationships: Papyrus (Underswap)/Reader, Sans (Horrortale)/Reader, Sans (Undertale)/Reader
Comments: 4
Kudos: 25





	1. Chapter 1

Hello, welcome to my first Undertale Oneshot book.

Enjoy!


	2. Countdown (Sans X Reader)

**Summary for the Chapter:**

> The soulmates trope.
> 
> Yes Sans is a skeleton but he still has his timer in the bones where his wrist is.

So I got this idea from another undertale story!

We're all born with a clock on our wrist. What is it for? Meeting your soulmate, of course.

Some people meet when they are kids, or some people wait decades to see the clock hit 0 and their soulmate to stand before them.

But monsters? They can end up waiting centuries, or even a thousand years, just for the one person they were born to be with.

Monsters were sometimes paired up with humans, but after the Great War, the monsters were trapped underground and never could to meet their soulmates, and their clock disappears, and they die all alone.

That's why Sans thought his clock was broken, it still counted down, even though he's met every single monster in the underground and human-monster pairings didn't exist anymore.

But still it counted. When he was created, it read 21 years, he'd have to wait a long time.

Now it read 1 year, 2 months, and 12 days. He was 20, and still hadn't met his soulmate. Papyrus was 18, and had met Mettaton 3 months ago. Sans didn't like it at first, but it was just meant to be.

Sans was losing hope. How could he meet his soulmate if he was underground? Does that mean the barrier would be broken soon?

1 year, 1 month, 11 days left

Sans couldn't get his timer to one year because of Flowey's constant resetting. He knew he'd never meet them now.

8 months and 16 days left

A couple months ago Sans had successfully scared the little weed into quitting his resets. Now all he had to do was wait.

4 months and 21 days left

Six. That's how many souls that Asgore had collected now. Six unfortunate humans had fell underground and died tragically.

One more and they would be free.

And Sans would meet his soulmate.

Sans had always suspected that his soulmate was different, but once he had met every monster through his many odd jobs, he had no doubt his clock was broken.

But when humans started falling, he knew he would meet them on the surface. They had to be human. He didn't want to admit to himself that if his clock was really broken he'd likely never meet them.

They just needed one more soul.

3 months and 17 days left

It was Sans' 21st birthday today. Everyone got together to throw him a big party, and they noticed he was quiet and sad most of the time.

It seemed he only smiled for his brother now.

2 months and 14 days left

Sans had started practicing his puns with the lady behind the door. He met her one day when he was doing a random knock-knock joke and she answered.

The woman helped him out sometimes too, he would often vent to her about when he would finally meet his soulmate. The woman said she was with her soulmate once, but decided to live on her own because her soulmate made a foolish mistake.

17 days left

Finally, Sans was so relieved he had finally gotten down to days. But he soon got worried. What if they didn't like monsters?

What if he was too messy? Too lazy? He really needed to sleep more but he lay awake many nights worrying about things.

14 days left

Sans was just sitting at his sentry post, like normal. But today was not normal. He only had two weeks left.

Yesterday the woman behind the door made him promise to protect any human that fell down. Sans didn't like making promises.

Then the ruins door creaked open. Sans heard it, and teleported high into a tree. It was a small child, with a striped sweater and messy brown hair.

Sans teleported close to the human and smashed the branch in the middle of the path.

The human jumped and turned, but Sans was faster.

The human finally got to the bridge Papyrus turned into a poorly made trap. Sans approached from behind.

"Human," he started. "Don't you know how to greet a new pal? Turn around and shake my hand." Sans spoke in a dark tone and cloaked his body in shadow.

The human turned slowly, and reached out to take his hand. The sound of a whoopee cushion filled the air and the shadows lifted.

The child laughed. Hard. Sans grinned. If all humans had that great of a sense of humor, no doubt his soulmate would love his jokes.

Sans talked to the human and they moved to the next area. There was a very conveniently shaped lamp and Sans kept hinting to it while talking to Papyrus but he didn't understand.

The kid moved on through the underground swiftly, and in two days, was at the castle.

12 days left

Sans didn't know how many times those numbers repeated on his wrist. Over and over, reset after reset, the kid kept restarting their adventure for seemingly no reason.

Sans even noticed that when they did reach the surface, his clock froze. It just stopped. It was like he was meant to meet them in a different ending.

So Sans knew the kid had something to do with it. The kid needed to go, or Sans would never meet his one and only.

This made him angry.

Very.

Very.

Angry.

So now, Sans stood in judgement hall. The kid was 6 feet away, looking nervous. That would make sense, with the sadistic smile on Sans' face.

Sans didn't care if this was a pacifist route. He was gonna end this kid, and scare them so bad they never set foot on the mountain again. Some other human would fall, and they would be sacrificed for the barrier.

Sans fought long and hard. Frisk did nothing but dodge, confused why Sans would suddenly try to kill them in a pacifist run.

Sans snuck bone attacks behind Frisk and pinned them to a pillar by impaling through their shoulders and shins. Frisk cried out in pain, blood running down the pillar.

Sans' smile widened and he simply shuffled over to Frisk. He slammed his fist right next to their head and Frisk flinched.

"Listen here you little brat...." Sans growled. "I'm done with your little games. If you ever.."

Sans summoned a sharp bone and shoved it through Frisk's stomach, causing a scream of pain.

"...EVER..." Sans twisted the bone. More screams.

"Show your face in the underground again, I will PERSONALLY make your life a L I V I N G H E L L." Sans' smile widened unnaturally.

He yanked the bone out. Tears streamed down Frisk's face. Sans raised his arm, and a massive Gaster blaster fizzled into existence. Sans' hand went higher and the blaster charged up.

"Now be a good little brat and reset and never, EVER return." Sans brought his hand down. The blaster fired. The smell of burning flesh filled the hall, and the kid's screams were covered by the high whine of pure energy.

Then the world fell away. Sans knew he went over the edge, but he had to scare the kid into never returning.

Sans landed on his bed as the world put itself back together. He looked at his wrist. Back to 17 days. He had three days before a human fell.

Sans spent the rest of the day sleeping, and Papyrus kept checking on him. Papyrus could tell he needed the sleep, so he let him be.

15 days left

Sans was still worried that Frisk would return, so he often spent time at Grillby's drinking ketchup and venting to Grillby.

Grillby didn't particularly understand what he was talking about, resets and genocidal children, but he nodded along, his good friend just needed to talk it out.

Today, though, Sans had to meet Toriel to make her little promise. Sans knew he couldn't keep it. Either way, whoever walked through that door would die.

If it was a normal human, he'd let Paps capture them and Undyne would do the hard part. If it was Frisk, he would kill them again.

But as he started talking to Toriel, she was as lively as ever, even knocking out new jokes. Sans was confused why she did not mention a new human.

Maybe they aren't coming today. That sounded right.

11 days left

It's been a while, and a human still hasn't fallen. Sans hoped they would fall soon, so he could be free to find his soulmate.

Sans had started to get worried that his clock would stop again. He had resorted to pulling his hoodie sleeves over his wrists so he couldn't see the clock.

9 days left

Sans had constant paranoia and anxiety that either the kid would return, a human wouldn't fall, or his clock would stop again.

He checked it every morning now, more anxious than excited.

6 days left

He had less than a week left. Sans had spent most of his time practicing his puns and stopped getting drunk. He wanted to be in good shape for his mate.

Toriel still hadn't mentioned a human, so Sans guessed he'd meet them right after they got to the surface.

3 days left

Sans often stayed awake at night imagining his soulmate. Papyrus was excited for him, just about everybody in Snowdin knew what was about to happen.

Sans hoped his soulmate was kind. It didn't matter what they looked like, he would love them all the same.

2 days left

Sans had been preparing things and he didn't even have time to look at his clock anymore.

He tidied up his room, prepping it for packing. He learned how to cook a variety of meals to suit his mate's taste.

Sans even stopped slacking off so much and starting saving up his money, after paying off Grillby's tab.

1 day left

Sans had been so anxious he wouldn't even look at his clock. He hadn't realized how low it was yet.

He was busy cooking breakfast for Papyrus and himself, well seasoned steak and eggs. Papyrus has been so proud of him lately, so Sans let him sleep in a bit so he could make them breakfast.

After breakfast, Sans went to the ruins door, and after talking to Toriel, learned a human had fallen last night.

Sans made the stupid promise half-heartedly and went to his sentry station. Nothing happened today, and Sans knew the human would come through tomorrow.

Sans got home, humming happily to himself, and baked up a nice marble cake just for the heck of it. He would bring it to the surface for his soulmate.

Once Papyrus got home and made dinner, Sans went off to bed. He had the best sleep in his life.

5 hours left

Sans had totally forgot about his timer at this point, and treated this morning just like any old morning.

He let Papyrus cook for today, and off to his station he went. He was there a few hours when he heard the scraping of the ruins door opening.

2 minutes left

Sans teleported high in the trees, and watched as a tall human exited the ruins with a big (f/c) hoodie on and the hood up.

He guessed this wasn't a kid, which was definitely different.

He did his whole routine of smashing the stick, but the human didn't seem that frightened. Strange.

Sans teleported behind the human and walked slowly up to them.

"Human." He began. "Don't you know how to greet a new pal? Turn around and shake my hand."

As Sans put his hand out, his sleeve pulled up to reveal his wrist, which he didn't notice. The human turned and shook his hand, but Sans was too distracted to laugh at the whoopee cushion or to look at the human.

His timer was at 0. The human must have noticed too, because they gasped. Sans held their hand tightly and pulled up their hoodie sleeve. Their timer was also at zero.

Sans looked up at the human with the biggest smile ever. "It's you. It's really you." Tears ran down Sans' bony cheeks and the human smiled kindly and pulled him in for a hug.

"So my soulmate's a skeleton. That's awesome." The human spoke.

Sans pulled away and got a good look at the human. They had sparkling (e/c) eyes and rosy cheeks. Their (h/c) hair moved softly in the wind. They were gorgeous.

Sans had a pun in mind. He smiled again. "Looks like I won't be bonely anymore." He winked.

The human's laughter was like tinkling bells. He loved it.

Sans put his hand back out, this time devoid of the whoopee cushion. "I'm Sans. Sans the skeleton."

The human put their hand in his again. "I'm (Y/N). (Y/N) the human."

Sans knew that he loved them with all his heart. He would protect them with his life.


	3. Little Doe | HT! Sans X Reader

**Summary for the Chapter:**

> Have a little bit of Axe being a cuddly sweetheart

In case you don't know, HT! Is HorrorTale.   
This is a version of the story where Frisk never fell and the core naturally ran out of power. If you've read the HorrorTale comic, Sans gets the hole in his skull because of Undyne. In this version, Asgore is still king and smashed his skull in with his trident because he couldn't fix the core in time.

Anyway, on to the story!  
~~~~~~~~~~~~

tap.. tap.. tap.. tap..

Sans tapped his phalanges on the wooden counter of his sentry station as he watched you interact with his brother.

You were an interesting human. You saw him and his brother, and instead of screaming or crying, you smiled and struck up a friendly conversation.

It infuriated Sans. His phalanges itched to grab his axe and send it hurtling through the air and cut through the soft flesh of your neck, but Paps seemed happy with you for now.

You even somehow convinced Paps that you weren't hungry and he just smiled and ate the human spaghetti himself.

Sans growled and his hand instinctively grabbed the outside of his eyesocket as he yanked on his orbital bone.

Sans knew that if he didn't kill you now, some lowlife monster would do it later and he wouldn't have any 'head dogs' to sell.

Sans chuckled. He didn't know how long it had been since the last time he had eaten anything, but he would never put human meat in his mouth. It disgusted him. 

No, he would save the meat for his brother and sell the leftovers for a nice price. For now, though, he would let his brother play with you until he got bored.

H O P E F U L L Y.

V E R Y.

S O O N...

~~Time Skip - Two Weeks Later~~

Well, Sans was definitely surprised. It took a week of Y/N dodging flying axes and hiding behind Papyrus before Sans was at least 'okay' with the human.

Y/N had started to live with the Skelebros and Papyrus was overjoyed, and even found ways to make food by foraging for plants and such.

She had befriended Alphys, and after the dinosaur monster had stopped trying to bite chunks of raw meat out of Y/N's arms, they were researching ways to break the barrier.

Sans, on the other hand, had become extremely protective of the human once she convinced him she wasn't trying to kill Paps. Not because he liked her or anything, just because Paps didn't want her to die, obviously.

Okay that was a lie. He liked Y/N. But he was too shy to admit it, so he just kept telling himself that this was the human he most tolerated.

So here they were, two weeks after Y/N walked out of those ruins doors. Sans was sitting on the dirty couch with Y/N wrapped up in his lap, his sharp phalanges softly running through her hair.

It had always been a nervous tick of his to pull on his eyesocket ever since the accident that destroyed part of Sans' skull and hindered some of his magic. The pain would often ground him.

He doesn't quite remember how it happened, it's all kinda fuzzy, but he did know his magic used to be blue before the underground started to starve.

But, since being on good terms with the human, running his fingers through her hair, or even simple physical contact, like a hug, seemed to calm him. He never really had anxiety attacks around her.

So here he was on a couch with the human, no, his human, playing with her hair as she pet his skull. She would giggle often at the deep rumbling purrs that emanated from Sans when she pet him.

He acted a lot like a cat around her. He would wrap her up in his jacket when they were out, and growl at anyone who got too close. He almost dusted a few monsters for trying to eat her, and he would purr and curl up around her at home.

Papyrus noticed this pretty quickly and made Sans tell him everything. Sans could never deny Papyrus when he makes that face where he makes his eyes so big and begs. 

Now, Paps would often 'try to get them together' by doing things like breaking dinner plates so they had to share or tripping Y/N so Sans has to catch her, which he always does.

Sans jumped out of his thoughts when he felt Y/N's fingers trailing over the jagged edge of the gaping hole on his skull. He felt his face heat up for some reason, and his hand shot out to grab her wrist.

Y/N looked up at him questioningly, and he met her gaze with his red eye. "Don't... that's a.. sensitive spot." Yeah, that should satiate her curiosity for now.

Yeah, it was sensitive. But not painful. It made Sans' face gain a red hue thinking about the feeling of Y/N's soft fingertips trailing along the edges of his gaping wound in his skull. It made him want to wrap her up in his hoodie and never let go.

She nodded and looked back to the t.v. as Sans released her wrist from his gentle hold. He knew humans were fragile so he made sure to be gentle with her, with his sharp phalanges and such.

So they sat there, cuddling, until Papyrus came home from foraging in a small cave he found in the forest with plants, actual growing plants. Still, Sans gave them the most food, because his human and his brother's needs came first.

~~Time Skip - The Next Day~~

"Sans! Sans! Wake Up!" Tiny hands poked at Sans' cheekbones as Y/N tried to wake him.

Sans grabbed her wrist without looking and peeked on of his eyes open. "I'm up, I'm up little doe." He grumbled.

Y/N turned red at the nickname and pulled her arm from his grasp, turning around instead to grab the t.v. remote. She was gonna ignore the name because she had no chance with Sans, at least that what she thought.

Sans rubbed his eyesockets and pushed himself up into a sitting position on the couch. They must have fallen asleep here last night.

He looked over the the clock that hung by the door and wasn't surprised to see that it was noon. He slept a lot, anyway.

He directed his attention to Y/N, who was changing channels on the t.v at a rapid pace. She seemed to have found the channel she was looking for, because she set the remote down on the coffee table and didn't hesitate to plop into Sans' lap.

It seemed to be a news broadcast, and of course the reporter was that red-and-black themed toaster of a robot, Mettaton. Sans' jaw dropped when he saw the title on the screen.

'THE SECRET HUMAN IN THE UNDERGROUND HAS BROKEN THE BARRIER' flashed across the screen.

Mettaton picked up the transcript and cleared his throat. "Hello monsters, Mettaton here with a breaking news broadcast! If you haven't been to Snowdin, this may come as a shock: There is a human living in the very house of the Serif brothers!"

He paused a moment to be dramatic. "But no eating this human! Because the human, with the help of the brilliant doctor Alphys, has finally broken the barrier!"

"We'll all be free! We can have normal food now instead of eating each other! King Asgore has requested that we not exit the underground until dawn tomorrow so we can prepare for the surface!" Y/N was glad she met Mettaton, he acts a little more like himself now, instead of trying to chop her up with a chainsaw.

Sans was overjoyed. He wanted to see the stars with all his soul. And thanks to the human wrapped up in his arms, he can.

-  
-  
-  
-

So here they were, all of the main monsters Y/N had managed to befriend and teach kindness to, finally standing in front of a beautiful sunrise.

"WHAT IS THAT BRIGHT THING?" Papyrus asked Sans.

"We call that the sun, bro." He smiled at the sight.

Everyone started walking off to explore the new world, and after Toriel hugged Y/N and raced after Asgore, Sans couldn't stop himself.

He picked Y/N up by the waist and spun her around, smiling. Then, surprisingly to both of them, he pulled her close and pressed his teeth to her lips. Sans was scared of rejection, but smiled when Y/N put her arms around his neck.

Sans pulled back and held her high. "You did it. You really did it." Sans was full of love and happiness, a feeling he missed for so long.

"I did it for you all." Was her response. "You deserve it."

And so, hand in hand, walked the skeleton and the human into the sunset.

"Hey Sans?"

"Yes?"

"I love you."

"I know you do."

"..."

"..."

"I love you too."

"Little Doe."

Edit: Changed Sans' nickname for the reader to fit his personality a bit more.


End file.
